G, Exposure for left temporal lobectomy. The exposure includes the frontal and temporal lobe, as might be used for extensive cortical recording and mapping. The exposure is greater than normally used for a standard temporal lobectomy. H, An approach that preserves more of the neocortical surface is to open through a sulcus like the occipitotemporal sulcus located between the inferior temporal and occipitotemporal gyri. I, The left temporal horn and hippocampal body and head have been exposed. The choroidal fissure has been opened by dividing the tenia fimbria that attaches the choroid plexus to the fimbria on the surface of the hippocampus. The choroid plexus remains attached to the thalamus. J, A temporal lobectomy has been completed. The third nerve, posterior cerebral artery, and tentorial edge are in the medial part of the exposure. A large bridging vein passes from the sylvian fissure below the temporal lobe to empty into a tentorial sinus. After disconnecting the hippocampus medially, the resection is extended across the head of the hippocampus behind the amygdala. (Images courtesy of AL Rhoton, Jr.)